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OWTS — Developer documentation

This site is the developer-facing view of OWTS: where the code lives, how the firmware + on-device UI fit together, and where to find the API/hardware references.

Repositories / code layout

  • Firmware (ESP-IDF): main/
    • The device HTTP server, REST API implementation, radio stack, sensors, and OLED UI.
  • Web UI (served by device): frontend/
    • Built into main/frontend/ (SPIFFS) and served under / by the firmware.
  • Documentation: docs/
    • docs/dev/: developer docs (this site)
    • docs/user/: end-user docs
  • API spec (OpenAPI JSON): docs/assets/api/openapi.json

What OWTS is (in one page)

OWTS is a local, on-device telemetry system intended to help make winch launches more consistent by transmitting the aircraft’s indicated airspeed (IAS) to the winch station with low latency.

Conceptually, OWTS uses two identical device builds with different roles:

  • One device per aircraft (transmitter):
    • measures IAS (MS4525DO) and transmits it over SX1262 using a compile-time modem choice (GFSK or LoRa; see OWTS_RADIO_USE_LORA_BACKEND in main/radio/owts_radio_settings.h).
  • One device at the winch (receiver):
    • receives aircraft IAS and presents it via:
      • a simple on-device web UI (served by the ESP32), and
      • a small REST API for configuration and status.

The key architectural idea is that the same firmware image can serve either role. It runs in two modes (aircraft / winch) and is configured into its role via NVS/API. This keeps hardware and deployment simple: the only difference between “aircraft” and “winch” is configuration, not a different codebase or PCB.

Proof of concept (not for operational use)

OWTS is currently a proof of concept. It is not recommended for operational use at this stage.

  • Radio compliance: the radio functionality is not yet certified for any specific operational scenario. Regulatory requirements vary by region.
  • Aircraft integration: installing or modifying aircraft sensors and connecting to pitot/static systems can be regulated and may require approvals depending on the country, the aircraft category, and local rules.
  • Safety: OWTS must not interfere with approved avionics or flight-critical systems. Treat the project as experimental development until the legal, technical, and operational aspects are validated.

Notes on scope

  • Dev docs are English-only.
  • Only the currently used hardware is documented here (Heltec V3.2 + MS4525DO).

Admonitions / callouts

This dev site uses Material for MkDocs admonitions for important caveats and workflow tips. See the upstream reference: mkdocs-material admonitions.